﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace NullableExample
{
    class Program
    {
        static void Main(string[] args)
        {
            int? a = null;

            a += 2;

            
            Console.WriteLine(a.GetValueOrDefault());
            Console.WriteLine(a.HasValue);
            Console.WriteLine(a.Value);

            Console.WriteLine();
            


        }
    }
}
